fix: guide URL out of date

Signed-off-by: Romain Beuque <[email protected]>

Author: rbeuque74

ovh/client.py

@@ -29,7 +29,8 @@
 It handles requesting credential, signing queries...
 
  - To get your API keys: https://eu.api.ovh.com/createApp/
- - To get started with API: https://api.ovh.com/g934.first_step_with_api
+ - To get started with API:
+ https://help.ovhcloud.com/csm/en-gb-api-getting-started-ovhcloud-api?id=kb_article_view&sysparm_article=KB0042784
 """
 
 import hashlib